Transformer effect
Encyclopedia
The transformer effect, or mutual induction, is one of the processes by which an electromotive force
(e.m.f.) is induced. In a transformer
, a changing electric current
in a primary coil creates a changing magnetic field
that induces a current in a secondary coil.
This process is one of two ways of inducing an electromotive force, the other being the relative motion of a current-carrying conductor within a magnetic field. This method relies on a conductor and magnetic field moving relative to one another, leading to a rate of change of flux, dΦ/dt. This can be explained further by Faraday's law of electromagnetic induction
and refined by Lenz's Law
.
Electromotive force
In physics, electromotive force, emf , or electromotance refers to voltage generated by a battery or by the magnetic force according to Faraday's Law, which states that a time varying magnetic field will induce an electric current.It is important to note that the electromotive "force" is not a...
(e.m.f.) is induced. In a transformer
Transformer
A transformer is a device that transfers electrical energy from one circuit to another through inductively coupled conductors—the transformer's coils. A varying current in the first or primary winding creates a varying magnetic flux in the transformer's core and thus a varying magnetic field...
, a changing electric current
Electric current
Electric current is a flow of electric charge through a medium.This charge is typically carried by moving electrons in a conductor such as wire...
in a primary coil creates a changing magnetic field
Magnetic field
A magnetic field is a mathematical description of the magnetic influence of electric currents and magnetic materials. The magnetic field at any given point is specified by both a direction and a magnitude ; as such it is a vector field.Technically, a magnetic field is a pseudo vector;...
that induces a current in a secondary coil.
This process is one of two ways of inducing an electromotive force, the other being the relative motion of a current-carrying conductor within a magnetic field. This method relies on a conductor and magnetic field moving relative to one another, leading to a rate of change of flux, dΦ/dt. This can be explained further by Faraday's law of electromagnetic induction
Faraday's law of induction
Faraday's law of induction dates from the 1830s, and is a basic law of electromagnetism relating to the operating principles of transformers, inductors, and many types of electrical motors and generators...
and refined by Lenz's Law
Lenz's law
Lenz's law is a common way of understanding how electromagnetic circuits must always obey Newton's third law and The Law of Conservation of Energy...
.